Vehicle front headlamp assemblies are conventionally mounted on a vehicle through the use of adjusters that provide aiming in the proper vertical and horizontal directions. In order to facilitate aiming in the proper vertical direction, bubble level assemblies have previously been utilized as separate components mounted on the headlamp assembly such as disclosed by U.S. Pat. Nos. 4,794,495 McMaham et al; 4,922,387 Ryder et al; and 4,970,629 McMahan.
Furthermore, such bubble levels, or spirit levels as they are often referred to due to the use of mineral spirits as the liquid in which the bubble is located, have also been mounted directly on a light housing so as to be viewable through a front lens of the associated headlamp assembly as disclosed by U.S. Pat. No. 4,916,583 Nagasawa.
Since tolerance variations affect the positioning of the lamp bulb element and the direction of the resultant beam that is reflected off of a reflector of a housing of the assembly, bubble level vials have also been previously mounted for adjustment as an assembly on headlamp lighting assemblies as disclosed by U.S. Pat. Nos. 4,660,128 Bergin et al and 4,802,067 Ryder et al.
Furthermore, U.S. Pat. No. 1,964,408 Stouffer et al which was noted by the investigation conducted in connection with the present invention discloses an adjustable bubble level that is utilized with a transit and is thus not deemed to be as relevant to the present invention as the prior art references cited above but is nevertheless being cited to make full disclosure of all prior art.